肿块型肝内胆管细胞癌:多排CT的动脉期强化与临床病理的相关性

Correlation between CT arterial enhancement patterns and clinicopathologic findings for intrahepatic mass-forming cholangiocarcinomas

目的:评估肿块型肝内胆管细胞癌(intrahepatic mass-forming cholangiocarcinomas,IMCCs)的CT的影像特征,重点分析动脉期强化的方式和程度,进而分析IMCCs典型动脉期强化与非典型强化两组的临床病理特点.方法:本研究回顾性分析了32例患者34个病理证实IMCCs病灶.均行多排CT平扫、动脉期、门脉期和/或平衡期的影像检查,根据肿瘤的形态和增强特点进行回顾性评估.依据肿瘤动脉期增强的体积是否>50%,将患者分为典型(强化体积>50%)和非典型两组;分别分析两组的影像特点与病理特点的相关性.并且比较两组的生存状况.生存率的计算依据Kaplan-Meier法,分析采用Long-rank检验,生存的多变量分析采用Cox proportional hazards模型.结果:24个IMCCs病灶(占71%)呈典型的动脉期强化;10个瘤灶(占29%)呈非典型性强化.非典型组的平均直径小于典型组的直径(P=0.001).慢性肝病多见于非典型组(P=0.021).动脉期强化的主要特点是周边和中央混合性不均匀强化.病理所见:同典型组比较,非典型组病灶的中央基质和坏死少、细胞面积较大,且胆管细胞成分多见.结论:IMCCs病灶的动脉期强化并不少见;动脉期的强化有助于与原发性肝细胞癌的鉴别,动脉期强化可作为病灶切除后生存期较长的独立性预后指标.

AIM： To evaluate the computed tomography （CT） imaging features of intrahepatic mass-forming cholangiocarcinomas （IMCCs）, with a special emphasis on the degree and pattern of arterial enhancement, and to determine whether the clinicopathologic features of IMCCs with arterial enhancement differ from those of IMCCs with less arterial enhancement. METHODS： Thirty-two patients with 34 pathologically confirmed IMCCs after surgical resection underwent multiphasic CT-unenhanced, hepatic arterial phase （HAP）, portal venous phase, and/or equilibrium phase imaging. CT images were retrospectively evaluated for tu-mor morphology and enhancement features. Patients were placed into typical or atypical enhancement groups according to the presence of enhancement in the largest volume （ 50%） of the tumors during the HAP. Imaging features of IMCCs were correlated with pathologic features. The typical and atypical enhancement groups were compared with respect to disease-free survival and overall survival. Survival rates were calculated by using the Kaplan-Meier method, and differences in survival were compared by using the log-rank test. A Cox proportional hazards model was used for multivariate survival analysis. RESULTS： Twenty-four （71%） of 34 IMCCs showed typical arterial enhancement, and 10 （29%） showed atypical enhancement. The mean diameter of atypical IMCCs was significantly smaller than that of typical IMCCs （P = 0.001）. Chronic liver disease was more frequent in the group with atypical lesions （P = 0.021）. During the HAP, the prevalent enhancement pattern in this group was a mixed pattern of peripheral rim and internal heterogeneous enhancement. At pathologic evaluation, atypically enhancing IMCCs showed less central stroma and necrosis and larger cellular areas and more frequently had a cholangiolocellular component than typically enhancing IMCCs. Arterial enhancement of IMCCs was found to be an independent prognostic factor for longer disease-free survival. CONCLUSION： Arterially enhancing IMCCs are not rare; thus, enhancement pattern analysis of arterially enhancing IMCCs will be helpful in differentiating them from hepatocellular carcinomas. In addition, arterial enhancement of IMCCs appears to correlate with disease-free survival.